"I'm just messing around with developer console command.
Here's some following commands below I used in this game.
sv_cheats 1 (to enable cheats)
god (cannot die)
noclip (to fly through walls)
sv_portal_placement_never_fail 1 (to make any surface portal conductive)
thirdperson (to enter third person perspective)
firstperson (to return back to first person perspective)"